In data transmission, in particular transmission of CAN messages using a CAN bus, the protocol overhead of the physical protocol associated with the CAN bus amounts to approximately 55%, i.e., the header part of the particular CAN message is greater than its useful data part or payload part.
Furthermore, the maximum possible symbol rate of a CAN bus is currently limited to approximately 1 Mbaud due the physical boundary conditions and, in particular, due to asymmetric delays on the CAN bus.